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1.
Article in Korean | WPRIM | ID: wpr-901197

ABSTRACT

Objective@#Aneurysmal subarachnoid hemorrhage (SAH) is a common emergency condition, resulting in high morbidity and mortality. The delta neutrophil index (DNI), which reflects the fraction of circulating immature granulocytes, is significantly associated with systemic inflammation after infection or sterile injury. Aneurysmal SAH also leads to systemic inflammation after a brain injury. This study aimed to evaluate the relationship between the DNI and poor neurologic outcomes in patients with aneurysmal SAH. @*Methods@#We retrospectively identified patients (>18 years old) with aneurysmal SAH consecutively admitted to the emergency department (ED) between January 1, 2011, and November 30, 2018. The diagnosis of aneurysmal SAH was confirmed using clinical and radiological findings. DNI was determined at 0, 24, 48, and 72 hours after ED admission. The primary result was a poor neurologic outcome using the modified Rankin scale. @*Results@#A total of 352 patients with aneurysmal SAH were included in this study. A multivariable logistic regression model revealed that a high value of DNI at 24 hours after ED admission was a strong independent predictor of poor neurologic outcome upon discharge (odds ratio [OR], 1.471; 95% confidence interval [CI], 1.081-2.001; P=0.014). Among patients with aneurysmal SAH, DNI >1.0% at 24 hours was significantly associated with poor neurologic outcomes upon discharge (OR, 5.037; 95% CI, 3.153-8.044; P<0.001). @*Conclusion@#DNI can be determined easily and rapidly after ED admission without any additional cost or time burden. A high DNI value at 24 hours after ED admission is significantly associated with a poor neurologic outcome upon discharge among patients with aneurysmal SAH.

2.
Article in English | WPRIM | ID: wpr-896718

ABSTRACT

Roseomonas aerofrigidensis is a gram-negative, strictly aerobic, non-motile bacterium, which was first isolated in 2017 in South Korea. We present the first report of the isolation of R.aerofrigidensis from the peritoneal fluid of a 38-year-old woman with a history of metastatic gastric cancer with peritoneal carcinomatosis. The isolate was resistant to cotrimoxazole. Further research on clinical and microbiological responses to several antibiotics are warranted.

3.
Article in Korean | WPRIM | ID: wpr-893493

ABSTRACT

Objective@#Aneurysmal subarachnoid hemorrhage (SAH) is a common emergency condition, resulting in high morbidity and mortality. The delta neutrophil index (DNI), which reflects the fraction of circulating immature granulocytes, is significantly associated with systemic inflammation after infection or sterile injury. Aneurysmal SAH also leads to systemic inflammation after a brain injury. This study aimed to evaluate the relationship between the DNI and poor neurologic outcomes in patients with aneurysmal SAH. @*Methods@#We retrospectively identified patients (>18 years old) with aneurysmal SAH consecutively admitted to the emergency department (ED) between January 1, 2011, and November 30, 2018. The diagnosis of aneurysmal SAH was confirmed using clinical and radiological findings. DNI was determined at 0, 24, 48, and 72 hours after ED admission. The primary result was a poor neurologic outcome using the modified Rankin scale. @*Results@#A total of 352 patients with aneurysmal SAH were included in this study. A multivariable logistic regression model revealed that a high value of DNI at 24 hours after ED admission was a strong independent predictor of poor neurologic outcome upon discharge (odds ratio [OR], 1.471; 95% confidence interval [CI], 1.081-2.001; P=0.014). Among patients with aneurysmal SAH, DNI >1.0% at 24 hours was significantly associated with poor neurologic outcomes upon discharge (OR, 5.037; 95% CI, 3.153-8.044; P<0.001). @*Conclusion@#DNI can be determined easily and rapidly after ED admission without any additional cost or time burden. A high DNI value at 24 hours after ED admission is significantly associated with a poor neurologic outcome upon discharge among patients with aneurysmal SAH.

4.
Article in English | WPRIM | ID: wpr-913381

ABSTRACT

Background@#Environmental sanitation plays a significant role on the prevalence of enteropathogenic bacteria. This study aimed to determine the trends in the prevalence and antimicrobial resistance profiles of enteropathogenic bacteria from 2011 to 2019. @*Methods@#A retrospective analysis was performed using data from stool cultures of Salmonella spp., Shigella spp., Plesiomonas shigelloides , Yersinia spp., Vibrio spp., and Campylobacter spp. Samples were obtained between 2011 and 2019 from Severance Hospital. Antimicrobial susceptibility profile was determined using the disk diffusion method for nontyphoidal Salmonella (NTS) and Campylobacterspp., following the Clinical and Laboratory Standards Institute (CLSI) guidelines. @*Results@#The number of specimens obtained for stool culture increased significantly from 13,412 during the period of 1969–1978, to 48,476 over the past nine years (2011–2019), whereas the ratio of positive specimens decreased significantly from 1,732 (12.9%) to 449 (0.9%). The proportion of samples positive for Salmonella Typhi decreased from 472 (93.6%, 1969–1978) to 4 (1.5%, 2011–2019), whereas the proportion of NTS increased from 14 (2.8%, 1969–1978) to 261 (96.7%, 2011–2019). Among all the enteropathogenic bacteria isolated, Shigella spp. accounted for 60.0% (1,039) isolates from 1969 to 1978, but only 1.6% (7) from 2011 to 2019. Campylobacter was the second most prevalent enteropathogenic bacteria, accounting for 29.4% isolates (132). Among the NTS strains isolated from 2016 to 2019, their susceptibility rates to ampicillin and sulfamethoxazole-trimethoprim were 51.1% and 85.2%, respectively. Additionally, the susceptibility rate of Campylobacter to ciprofloxacin was 15.8%. @*Conclusion@#The prevalence of Salmonella Typhi and Shigella spp. significantly decreased, whereas those of NTS and Campylobacter spp. increased. Therefore, continuous monitoring of ciprofloxacin-resistant Campylobacter spp. is of vital importance.

5.
Article in English | WPRIM | ID: wpr-874188

ABSTRACT

Background@#One health is a flexible concept with many facets, including the environment, community, and the nosocomial super-bacteria resistance network. We investigated the molecular prevalence of extended-spectrum-β-lactamase-producing Escherichia coli (ESBL-EC) in workers, livestock, and the farm environment in Korea. @*Methods@#ESBL-EC isolates were obtained from samples from 19 swine farms, 35 retail stores, seven slaughterhouses, and 45 related workers throughout Korea from August 2017 to July 2018, using ChromID ESBL (BioMérieux, Marcy l’Etoile, France) agar and enrichment broth. The presence of ESBL and mobilized colistin resistance (mcr) genes and antimicrobial resistance were determined. Clonality was evaluated with pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). @*Results@#In total, 232 ESBL-EC isolates were obtained from 1,614 non-duplicated samples (14.4% positive rate). The ESBL-EC isolates showed regional and source-related differences. blaCTX-M-55 (N = 100), blaCTX-M-14 (N = 65), blaCTX-M-15 (N = 33), and blaCTX-M-65 (N = 23) were common ESBL types. The ESBL-EC isolates showed high resistance rates for various antimicrobial classes; however, all isolates were susceptible to carbapenem. One swine-originating colistin-resistant isolate did not carry any known mcr gene. PFGE was successful for 197 of the 232 isolates, and most PFGE types were heterogeneous, except for some dominant PFGE types (O, R, T, U, and V). MLST of 88 isolates was performed for representative PFGE types; however, no dominant sequence type was observed. @*Conclusions@#The proportion of ESBL-EC in swine industry-related samples was significant, and the isolates harbored common clinical ESBL gene types. These molecular epidemiologic data could provide important evidence for antimicrobial-resistance control through a one health approach.

6.
Article in English | WPRIM | ID: wpr-874170

ABSTRACT

In response to the ongoing coronavirus disease 2019 (COVID-19) pandemic, an online laboratory surveillance system was established to monitor severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) real-time reverse transcription-PCR (rRT-PCR) testing capacities and results. SARS-CoV-2 rRT-PCR testing data were collected from 97 clinical laboratories, including 84 medical institutions and 13 independent clinical laboratories in Korea. We assessed the testing capacities to utilize SARS-CoV-2 rRT-PCR based on surveillance data obtained from February 7th to June 4th, 2020 and evaluated positive result characteristics according to the reagents used and sample types. A total of 1,890,319 SARS-CoV-2 rRT-PCR testing were performed, 2.3% of which were positive. Strong correlations were observed between the envelope (E ) gene and RNA-dependent RNA polymerase (RdRp )ucleocapsid (N ) genes threshold cycle (Ct) values for each reagent. No statistically significant differences in gene Ct values were observed between the paired upper and lower respiratory tract samples, except in the N gene for nasopharyngeal swab and sputum samples. Our study showed that clinical laboratories in Korea have rapidly expanded their testing capacities in response to the COVID-19 outbreak, with a peak daily capacity of 34,193 tests. Rapid expansion in testing capacity is a critical component of the national response to the ongoing pandemic.

7.
Article in English | WPRIM | ID: wpr-889014

ABSTRACT

Roseomonas aerofrigidensis is a gram-negative, strictly aerobic, non-motile bacterium, which was first isolated in 2017 in South Korea. We present the first report of the isolation of R.aerofrigidensis from the peritoneal fluid of a 38-year-old woman with a history of metastatic gastric cancer with peritoneal carcinomatosis. The isolate was resistant to cotrimoxazole. Further research on clinical and microbiological responses to several antibiotics are warranted.

9.
Article in English | WPRIM | ID: wpr-899702

ABSTRACT

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 not yet has established its treatment, but convalescent plasma has been expected to increase survival rates as in the case with other emerging viral infections. We describe two cases of COVID-19 treated with convalescent plasma infusion. Both patients presented severe pneumonia with acute respiratory distress syndrome and showed a favorable outcome after the use of convalescent plasma in addition to systemic corticosteroid. To our knowledge, this is the first report of the use of convalescent plasma therapy for COVID-19 in Korea.

10.
Article in English | WPRIM | ID: wpr-891998

ABSTRACT

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 not yet has established its treatment, but convalescent plasma has been expected to increase survival rates as in the case with other emerging viral infections. We describe two cases of COVID-19 treated with convalescent plasma infusion. Both patients presented severe pneumonia with acute respiratory distress syndrome and showed a favorable outcome after the use of convalescent plasma in addition to systemic corticosteroid. To our knowledge, this is the first report of the use of convalescent plasma therapy for COVID-19 in Korea.

13.
Article | WPRIM | ID: wpr-830437

ABSTRACT

The outbreak of coronavirus disease 2019 (COVID-19), which began in December 2019, is still ongoing in Korea, with >9,000 confirmed cases as of March 25, 2020. COVID-19 is a severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) infection, and real-time reverse transcription-PCR is currently the most reliable diagnostic method for COVID-19 around the world. Korean Society for Laboratory Medicine and the Korea Centers for Disease Prevention and Control propose guidelines for diagnosing COVID-19 in clinical laboratories in Korea. These guidelines are based on other related domestic and international guidelines, as well as expert opinions and include the selection of test subjects, selection of specimens, diagnostic methods, interpretation of test results, and biosafety.

14.
Article | WPRIM | ID: wpr-830355

ABSTRACT

Background@#The rapid antimicrobial susceptibility testing (AST) performed on urine samples would guide the adequate choice of antibiotics for obtaining better treatment outcomes in patients. Our study aimed to evaluate the performance of the modified-EUCAST (European Committee on Antimicrobial Susceptibility Testing) rapid direct AST on urine samples. @*Methods@#From >2,000 urine samples, a total of 128 urine samples containing bacterial counts of ≥2 × 10 4 CFU/mL with a uniform bacterial shape were initially included based on flow cytometry (Sysmex UF-1000i, Japan) and Gram staining, respectively. A total of 103 samples showing the presence of Enterobacteriaceae were finally selected in this study. The urine samples were directly inoculated on Mueller-Hinton agar, which was used in the current EUCAST rapid direct AST on blood samples. The size of the growth inhibition zones around antimicrobial disks was measured using a digital scanner (BIOMIC vision analyzer, Giles scientific, USA) and further confirmed by visualization with naked eyes after incubation for 4, 6, and 8 hours. The AST interpretations were compared to those of the conventional VITEK 2 AST system (bioMérieux, France) and the discrepancies between both tests were confirmed with the E-test. @*Results@#The antibiotics, namely ampicillin, cefazolin, aztreonam, ceftazidime, cefotaxime, cefoxitin, cefepime, gentamicin, ciprofloxacin, and cotrimoxazole showed excellent correlations with modified-EUCAST rapid direct test and conventional ASTs with >0.75 weighted kappa values. The categorical agreement of the rapid direct AST was 1,442 (93.3%), with 76 (4.9%) minor error, 9 (0.6%) major error and 18 (1.2%) very major error, implicating the reliability of this method for clinical application. @*Conclusion@#Performing the modified-EUCAST rapid direct AST on urine samples can predict reliable AST results within 8 hours. The rapid direct AST can help the physicians to initiate adequate antimicrobial treatment for urinary tract infections.

15.
Article in Korean | WPRIM | ID: wpr-762289

ABSTRACT

BACKGROUND: Salmonella is an important pathogen that causes gastroenteritis and sepsis in humans. Recently, changes in serotype prevalence and an increase in antimicrobial resistance have been reported. This study investigated the distribution of Salmonella serotypes and determined the antimicrobial susceptibility of various strains. METHODS: We collected 113 Salmonella isolates other than Salmonella serotype Typhi from 18 university hospitals in 2015. The serotypes were identified by Salmonella antisera O and H according to the Kauffman White scheme. Antimicrobial susceptibility tests for 12 antibiotics were performed using the disk diffusion method or E-test. RESULTS: We identified 22 serotypes. Serotype group B (44.2%) was the most common, followed by groups C (34.5%) and D (21.2%). Salmonella I 4,[5],12:i:- (23.0%), S. Enteritidis (16.8%), and S. Typhimurium (12.4%) were the most common species. Resistance rates for ampicillin, chloramphenicol, ceftriaxone, and trimethoprim/sulfamethoxazole were 46.9%, 18.5%, 8.8%, and 5.3%, respectively. The intermediate resistance rate to ciprofloxacin was 29.2%. Six isolates were extended-spectrum β-lactamase (ESBL) producers, including 5 bla(CTX-M-15) and 1 bla(CTX-M-55). CONCLUSION: There have been changes in the serotype prevalence and antimicrobial resistance of Salmonella in Korea, with a high prevalence of CTX-M 15-positive strains. Continuous monitoring of Salmonella serotypes and antimicrobial resistance is warranted.


Subject(s)
Ampicillin , Anti-Bacterial Agents , Ceftriaxone , Chloramphenicol , Ciprofloxacin , Diffusion , Gastroenteritis , Hospitals, University , Humans , Immune Sera , Korea , Methods , Prevalence , Salmonella , Sepsis , Serogroup , Serotyping
16.
Article in Korean | WPRIM | ID: wpr-762288

ABSTRACT

BACKGROUND: Antimicrobial resistant continues to pose a threat to public health. Therefore, rapid and accurate antimicrobial susceptibility testing is very important. The objectives of this study were to evaluate the performance of the MicroScan system (Beckman Coulter, USA) with newly developed Korean Antimicrobial Susceptibility Testing Panels (KSCM panels) for antimicrobial susceptibility testing (AST) against clinical isolates in South Korea. METHODS: Three KSCM panels were designed in this study. For the performance evaluation, a total of 1,325 clinical isolates including 1,027 of Gram-negative bacilli and 298 Gram-positive cocci collected from eight general hospitals in South Korea were used. The results by KSCM panels were compared with those by conventional methods. RESULTS: By KSCM-1 panel for Gram-positive cocci, the rates of categorical agreement (CA) were >90% in all the antimicrobials tested in this study. The rates of major error (ME) were also 90%, ME rates <3%, and VME rates <1.5%. CONCLUSION: The newly developed three KSCM panels for MicroScan system (Beckman Coulter) showed excellent performance in AST against a large number of clinical isolates, and they are applicable to clinical microbiology laboratories.


Subject(s)
Ampicillin , Enterobacteriaceae , Gram-Positive Cocci , Hospitals, General , Hospitals, Teaching , Korea , Public Health , Tetracycline
17.
Article in English | WPRIM | ID: wpr-739143

ABSTRACT

BACKGROUND: The emergence of carbapenem resistance among gram-negative bacilli (GNB), mediated by carbapenemase production, has necessitated the development of a simple and accurate device for detecting minimum inhibitory concentrations (MICs) and resistance mechanisms, especially carbapenemase production. We evaluated the performance of the BD Phoenix NMIC-500 panel (BD Diagnostic Systems, Sparks, MD, USA) for antimicrobial susceptibility testing (AST) and carbapenemase-producing organism (CPO) detection. METHODS: We used 450 non-duplicate clinical GNB isolates from six general hospitals in Korea (409 Enterobacteriaceae and 41 glucose non-fermenting bacilli [GNFB] isolates). AST for meropenem, imipenem, ertapenem, ceftazidime, and ceftazidime/avibactam, and CPO detection were performed using the Phoenix NMIC-500 panel. Broth microdilution was used as the reference method for AST. The rates of categorical agreement (CA), essential agreement (EA), minor error (mE), major error (ME), and very major error (VME) were calculated in each antimicrobial. In addition, PCR and sequencing were performed to evaluate the accuracy of CPO detection by the BD Phoenix NMIC-500 panel, and the rate of correct identification was calculated. RESULTS: The CA rates were >90% for all antimicrobials tested with the Enterobacteriaceae isolates, except for imipenem (87.2%). The GNFB CA rates ranged from 92.7% to 100% for all antimicrobials. The ME rates were 1.7% for Enterobacteriaceae and 0% for GNFB. The panel identified 97.2% (243/250) of the carbapenemase-producing isolates. CONCLUSIONS: The BD Phoenix NMIC-500 panel shows promise for AST and CPO detection.


Subject(s)
Ceftazidime , Drug Resistance, Bacterial , Enterobacteriaceae , Glucose , Hospitals, General , Imipenem , Korea , Methods , Microbial Sensitivity Tests , Polymerase Chain Reaction
18.
Article in English | WPRIM | ID: wpr-739013

ABSTRACT

BACKGROUND: Escherichia coli and Klebsiella pneumoniae clinical isolates producing CTX-M extendedspectrum β-lactamases (ESBLs) were assessed for antimicrobial resistance phenotypes varied by group of enzymes. METHODS: A total of 1,338 blood isolates, including 959 E. coli and 379 K. pneumoniae, were studied. All the strains were collected between January and July 2017 from eight general hospitals in South Korea. The species were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Antimicrobial susceptibilities were determined by disk diffusion methods and ESBL phenotypes by double-disk synergy tests using disks containing cefotaxime, ceftazidime, cefepime, aztreonam, and clavulanic acid (CA). The genes for β-lactamases were identified by PCR and sequencing. RESULTS: Of total microbes, 31.6% (303/959) E. coli and 24.0% (91/379) K. pneumoniae were resistant to cefotaxime and 28.1% (269/959) E. coli and 20.1% (76/379) K. pneumoniae were CTX-M-type ESBL producers. Among the detected CTX-M ESBLs, 58.0% (156/269) in E. coli and 86.8% (66/76) in K. pneumoniae belonged to group 1, 46.8% (126/269) in E. coli and 14.5% (11/76) in K. pneumoniae were group 9. Ten E. coli and one K. pneumoniae isolates co-produced both groups of CTX-M ESBL. The group 1 CTX-M producers had a higher level of resistance to cefotaxime, ceftazidime, cefepime, and aztreonam and exhibited stronger synergistic activities when combined with CA compared to group 9. CONCLUSION: ESBL phenotypes differ by CTX-M ESBL group and phenotype testing with drugs including 4th generation cephalosporins and monobactams is critical for screening CTX-M-producers with better sensitivity.


Subject(s)
Aztreonam , Cefotaxime , Ceftazidime , Cephalosporins , Clavulanic Acid , Diffusion , Escherichia coli , Hospitals, General , Klebsiella pneumoniae , Korea , Mass Screening , Mass Spectrometry , Monobactams , Phenotype , Pneumonia , Polymerase Chain Reaction
19.
Article in English | WPRIM | ID: wpr-718328

ABSTRACT

BACKGROUND: The increasing morbidity and mortality rates associated with Acinetobacter baumannii are due to the emergence of drug resistance and the limited treatment options. We compared characteristics of colistin-resistant Acinetobacter baumannii (CR-AB) clinical isolates recovered from patients with and without prior colistin treatment. We assessed whether prior colistin treatment affects the resistance mechanism of CR-AB isolates, mortality rates, and clinical characteristics. Additionally, a proper method for identifying CR-AB was determined. METHODS: We collected 36 non-duplicate CR-AB clinical isolates resistant to colistin. Antimicrobial susceptibility testing, Sanger sequencing analysis, molecular typing, lipid A structure analysis, and in vitro synergy testing were performed. Eleven colistin-susceptible AB isolates were used as controls. RESULTS: Despite no differences in clinical characteristics between patients with and without prior colistin treatment, resistance-causing genetic mutations were more frequent in isolates from colistin-treated patients. Distinct mutations were overlooked via the Sanger sequencing method, perhaps because of a masking effect by the colistin-susceptible AB subpopulation of CR-AB isolates lacking genetic mutations. However, modified lipid A analysis revealed colistin resistance peaks, despite the population heterogeneity, and peak levels were significantly different between the groups. CONCLUSIONS: Although prior colistin use did not induce clinical or susceptibility differences, we demonstrated that identification of CR-AB by sequencing is insufficient. We propose that population heterogeneity has a masking effect, especially in colistin non-treated patients; therefore, accurate testing methods reflecting physiological alterations of the bacteria, such as phosphoethanolamine-modified lipid A identification by matrix-assisted laser desorption ionization-time of flight, should be employed.


Subject(s)
Acinetobacter baumannii , Acinetobacter , Bacteria , Colistin , Drug Resistance , Humans , In Vitro Techniques , Lipid A , Masks , Methods , Molecular Typing , Mortality , Population Characteristics
20.
Article in English | WPRIM | ID: wpr-718327

ABSTRACT

BACKGROUND: The emerging mobile colistin resistance gene, mcr-1, is an ongoing worldwide concern and an evaluation of clinical isolates harboring this gene is required in Korea. We investigated mcr-1-possessing Enterobacteriaceae among Enterobacteriaceae strains isolated in Korea, and compared the genetic details of the plasmids with those in Escherichia coli isolates from livestock. METHODS: Among 9,396 Enterobacteriaceae clinical isolates collected between 2010 and 2015, 1,347 (14.3%) strains were resistant to colistin and those were screened for mcr-1 by PCR. Colistin minimum inhibitory concentrations (MICs) were determined by microdilution, and conjugal transfer of the mcr-1-harboring plasmids was assessed by direct mating. Whole genomes of three mcr-1-positive Enterobacteriaceae clinical isolates and 11 livestock-origin mcr-1-positive E. coli isolates were sequenced. RESULTS: Two E. coli and one Enterobacter aerogenes clinical isolates carried carried IncI2 plasmids harboring mcr-1, which conferred colistin resistance (E. coli MIC, 4 mg/L; E. aerogenes MIC, 32 mg/L). The strains possessed the complete conjugal machinery except for E. aerogenes harboring a truncated prepilin peptidase. The E. coli plasmid transferred more efficiently to E. coli than to Klebsiella pneumoniae or Enterobacter cloacae recipients. Among the three bacterial hosts, the colistin MIC was the highest for E. coli owing to the higher mcr-1-plasmid copy number and mcr-1 expression levels. Ten mcr-1-positive chicken-origin E. coli strains also possessed mcr-1-harboring IncI2 plasmids closely related to that in the clinical E. aerogenes isolate, and the remaining one porcine-origin E. coli possessed an mcr-1-harboring IncX4 plasmid. CONCLUSIONS: mcr-1-harboring IncI2 plasmids were identified in clinical Enterobacteriaceae isolates. These plasmids were closely associated with those in chicken-origin E. coli strains in Korea, supporting the concept of mcr-1 dissemination between humans and livestock.


Subject(s)
Colistin , Enterobacter aerogenes , Enterobacter cloacae , Enterobacteriaceae , Escherichia coli , Escherichia , Genome , Humans , Klebsiella pneumoniae , Korea , Livestock , Microbial Sensitivity Tests , Plasmids , Polymerase Chain Reaction
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